This invention relates generally to auxiliary apparatus for single and multiple spindle machines and more specifically to an apparatus for increasing the speed of a single spindle of a single or multiple spindle machine which is driven directly by the machine and mounts to the tool slide.
Lathes, automatic screw machines and multiple spindle machines comprise the fundamental production means for parts which may be characterized as having axial symmetry. For example, shafts, flanges, collars, bushings, bearings, screws, bolts, fasteners, fittings and innumerable other machine and structural components are so fabricated. Given the pervasive nature of both the machine and the components thereon fabricated, much attention and effort has been directed not only to the design, configuration and function of the basic machines, but also to modifications of such machines and attachments therefor.
Such a lathe attachment is disclosed in U.S. Pat. No. 332,817. This attachment is intended to increase the size of the workpiece which may be mounted upon a lathe and includes an enlarged face plate which is supported for rotation upon a demountable base and a speed reducing drive which derives power from the existing lathe. While the faceplate thus turns slower than the original design speed, it accepts a significantly larger work piece than accommodated by the basic lathe.
An attachment intended to facilitate milling or turning and to increase the swing of a lathe is disclosed in U.S. Pat. No. 1,028,728. The lathe attachment mounts to the lathe bed and includes a frame supporting a plurality of interengaging gears. The input and output shafts of the gearing include beveled gears which mate with complemental beveled gears disposed upon and coupled to splined shafts. Accordingly, the positions of the input and output shafts along the splined shafts may be adjusted. Consequently, the maximum size of workpieces accepted by the lathe can be increased for various milling and turning processes.
U.S. Pat. No. 1,054,387 teaches yet another attachment for lathes wherein an oversized work piece may be received within a hollow gear. The hollow gear is driven through an offset shaft by a drive gear on the spindle. A cutting tool disposed upon and rotated with the hollow gear engages the surface of the workpiece, rotating about it and turning and truing it.
In U.S. Pat. No. 1,311,454, a supplementary high speed lathe spindle is disclosed. The device is straightforward and includes a bearing member and stub shaft which are mounted upon and secured to the headstock spindle of the lathe. A cone pulley and supplemental nose piece supported for rotation on the stub shaft are driven by independent power means and may rotate at speeds higher or, presumably, lower, than the normal lathe speed. Since the lead screw is driven by the internal lathe drive, the ratio of spindle revolutions relative to tool feed travel may be raised significantly and adjusted independently.
In U.S. Pat. No. 3,555,963 a machine is illustrated which includes a removable multi-tool head. A conveyor or transfer mechanism provides and removes both workpieces and multiple tool holding heads. Production increases are offered by this machine which can rapidly exchange tool heads containing several tools.
A spindle machine having plural interchangeable gear boxes is disclosed in U.S. Pat. No. 3,794,436. This machine utilizes a plurality of interchangeable gear boxes which are driven by a single drive gear and which each include a plurality of output shaft spindles. The spindles may be driven by different gear train configurations to provide different takeoff speeds. The takeoffs are connected through universal drive assemblies to conventional spindles.
A friction controlled tool holder for lathes is disclosed in U.S. Pat. No. 3,840,928. This device includes a stub shaft for mounting in the spindle of a lathe and a pinion gear clutching arrangement which is surrounded by a manually engageable cylindrical sleeve. When rotation of the sleeve is manually retarded, power is transferred to a tapping or other cutting tool and the tool performs a cutting operation. When the sleeve is released, the cutting action ceases.
Finally, U.S. Pat. No. 4,722,123 teaches a dual speed drive system for lathes. An electric motor is coupled to and rotates the workpiece and provides power to a hydraulic pump. The pump is preferably a variable volume type and its output flow is coupled to a hydraulic motor which drives the tool. Hence, the speed of the tool may be adjusted independently of the speed of the electric motor and thus of the workpiece to provide a wide range of relative tool and workpiece speeds.
The foregoing survey of lathe and spindle machine attachments is representative of the various features, adaptations and goals relating to modifications of such machines. However, it is also apparent that further improvements directed toward spindle drive systems and consequent productivity increases are both possible and desirable.